DE 10 2009 042 981 A1 has disclosed an intercooler of the generic type having an air inlet tank and an air outlet tank and having a condensate collector for collecting condensate which is separated in the intercooler. Moreover, a condensate line is provided which is connected via an inlet to the condensate collector and via an outlet to an air intake manifold. By way of this, condensate extraction in a manner which is dependent on the differential pressure from the condensate collector is to be brought about during operation of the intercooler, as a result of which, in particular, previously used actuators, flaps and/or controllers can be dispensed with.
DE 10 2009 011 634 A1 has in turn disclosed an intercooler of the generic type, in which a condensate line continuously extracts condensate from the condensate collector as a reaction to a gradient which is generated by a throttle flap, if an engine is situated in the switched-on state.
DE 10 2008 045 685 A1 has disclosed an internal combustion engine arrangement having an internal combustion engine, a charge air compressor, a low pressure exhaust gas recirculation means, an intercooler and a charge air line. It is provided here that the intercooler has a closable condensate discharge opening at the lowest point, which condensate discharge opening is connected by way of a condensate discharge line to the charge air line. As a result, it is to be made possible to control a condensate discharge into the charge air line.
In general, depending on the environmental conditions (temperature and relative air humidity) and the present operating conditions, it can occur that condensate accrues in the intercooler; firstly preferably at low load and low boost pressure and secondly in the case of a low pressure exhaust gas recirculation application. As a result, an impairment of the charge air cooling operation can firstly occur, in particular at an ambient temperature below freezing point, at which the condensate which is collected can freeze. As a result, the passage of the charge air through the intercooler is blocked partially. Far more critical, however, is the volume expansion of the water when freezing, which can result in a burst pipe of the intercooler. The internal combustion engine can also be subject partially to irreparable damage as a result of the sudden entry of the entire, collected condensate into the said internal combustion engine.
For this reason, it is known from the prior art to avoid condensate in the intercooler or to discharge it from the intercooler, to which end, for example, flaps which are operated by means of actuators are provided for this purpose. Bypass lines around the intercooler are also known. In addition, it is known from the prior art to extract the condensate constantly and without additional actuators or flaps on account of a differential pressure between an air intake manifold and a condensate collector at the intercooler.
It is disadvantageous in the solutions which are known from the prior art, however, that they are either expensive and structurally complex, for example in the case of flaps which are controlled by means of actuators with an associated control logic means, are less effective, for example in the case of bypass lines or constantly open condensate discharge openings, via which a certain proportion of the charge air flow always escapes, or are even fragile, if the condensate is collected in external condensate collectors and can freeze there at correspondingly low exterior temperatures and can cause damage as a result.